Impacted casing method for installing anchor piles or tiebacks in situ

ABSTRACT

Method and means for providing pile body in an earth situs, includes driving casing into situs to define a cavity of required depth. An auger positioned within the casing is rotatable in screwing direction to remove earth from defined cavity, and carries expansible cutter means rotatable with auger to enlarge cavity girth below inner end of casing. Earth removed from casing and cavity enlargement is replaced with different material, such as self-hardenable cement, to form pile body with load carrying enlargement at inner end of casing.

United States Patent 1191 Turzillo 1 1 Feb. 11, 1975 [541 IMPACTED CASING METHOD Fon 3,479,829 11/1969 000111111111 (ml/53.64 x

INSTALLING ANCHOR FILES OR FOREIGN PATENTS 0R APPLICATIONS TIEBACKS IN SlTU 82] M969 Inventor: Lee A. Turzillo, 2078 Glengary Rd.,

Akron, Ohio 44312 Filed: Sept. 18, 1973 Appl. No.: 398,311

U.S. Cl 61/53.6, 61/5362, 175/171, 175/286, 175/394 Int. Cl. E02d 5/38, E02d 5/44, E21c 17/00 Field of Search 61/536, 53.62. 53.64, 61/5366, 53.52, 53.5; 175/394, 286,171

References Cited UNITED STATES PATENTS Canada 175/171 Primary Examiner tlacob Shapiro [57] ABSTRACT Method and means for providing pile body in an earth 12 Claims, 8 Drawing Figures Pmtmwmnms sum 20F 2 M MJ M 2 iii;

BACKGROUND OF INVENTION I-Ieretofore concrete pile bodies have been variously installed in situ by driving a metal casing into the situs to define a pile cavity and removing the displaced earth through the casing, as by pumping in pressurized jetting fluid. In use of such methods, however, there was no dependable way to provide a bulb-forming cavity enlargement at the inner of the casing without use ofcomplicated and/or expensive equipment, and in at least some instances it was not possible to control the size, shape or location of the formed bulb.

In Goodman U.S. Pat. No. 3,479,829, for example, an elongated tubular member, having pivoted fins near the lower end thereof, is said to be sonically driven into an earth formation while a slurry of solidifiable material is injected into the formation, from ports adjacent the fins, to form an enlarged base. The tubular member is said to be then withdrawn from the formation while continuing to pump slurry to form a pile. No means, however, is provided in Goodman for effective removal ofthe drilled earth, and there is no means provided for accurately accomplishing movement of the fins to control the shape and axial extent of the cavity enlargement which forms the base.

Watson U.S. Pat. Re 27,498 discloses provision of a Kelly bar on which the lowermost portion of auger flighting is provided with a single relatively fixed blade, a portion of which extends radially to clean" the wall of a bore formed in the earth by the auger flighting. Accordingly, the Watson Kelly bar could not function for operation through a tubular casing which has been driven into the situs, particularly because the cutter blade is affixed to the auger flighting.

SUMMARY OF INVENTION In practice of the method of the present invention for producing a concrete pile, for example, a tubular metal casing of requisite length is driven into the earth of a situs to predetermined depth, as by, use of known impaction means. A hollow-shafted auger, adapted to be retained through the casing with the earth of the defined cavity contained along continuous flighting of the auger, may have a radially expansible cutting device rotatable with the auger when positioned beyond the inner end of the casing, to cut into the earth and form a cavity enlargement of desired depth determined by axial movement of the auger. By retraction of the cutting device and axial withdrawal and rotation of the auger, the augered earth may be removed from the situs and replaced by feeding self-hardenable cementitious material along the auger flighting while withdrawingthe auger from the casing, thereby to form a pile body having a bulb enlargement of selectively controlled size and shape.

A general object of the present invention is to provide an improved method and means for forming concrete, tension or anchor piles of the character referred to in the background of invention, by which the location and axial extent of the bulb-forming cavity enlargement can be accurately controlled.

Other objects of the invention will be manifest from the following brief description and the accompanying drawings.

Of the accompanying drawings:

FIG. I is view, partly broken away and in-crosssection illustrating use of one form of drilling apparatus of the invention, in an initial step of driving 'a tubular metal casing into earth of a situs to define a partial pile cavity, and insertion of a hollow shafted auger through the casing, for removal of the earth from the cavity.

FIG. 2 is a cross-sectional view corresponding to FIG. 1, illustrating injection of the casing to full predetermined depth and operation of the auger for removal of all earth cavity, including the earth'moved from a cavity enlargement formed below the end of the casing, as

by self-operating expansion of a spring-like extension of the auger flighting.

FIG. 3 is a cross-sectional view corresponding to the lower end portion of FIG. 2, but illustrating a condition in which the earth has been removed from the fully defined cavity, as shown in FIG. 2, and replaced with selfhardenable cementitious material to form a pile or like body, with or without a tension rod or like member axially centered therethrough.

FIGS. 4 and 5 are cross-sectional views corresponding to the lower ends of FIGS. 1 and 2, respectively,- lustrating use of a modified form of self-operating cav ity enlarging mechanism.

FIGS. 6 and 7 are views corresponding to FIGS. 4 and 5 respectively, illustrating use of another modified form of self-operating cavity enlarging mechanism.

FIG. 8 is a view corresponding to FIGS. 2, 5 and 7, and illustrates a modified form of cavity enlarging cutter means adapted to be mechanically operated from a point above ground.

With particular reference to FIGS. 1 and 2, apparatus used for the method of the invention may include use of a hollow-shafted, spiral flighted auger 10, the flighting 10a of which is adapted to be slidably and rotatably received in a thin-walled, rigid metal tube or casing 11. An extension 12a of the auger shaft 12 may have a pilot bit 14 suitably mounted on the free inner end portion of said extension 12a, for predetermined limited axial movement thereon, and a corresponding section of auger flighting 15, made of relatively thin springy material, is anchored at spaced ends thereof to the movable bit 14 and the end portion 16 of the auger shaft 12, said springy flighting 15 being designed yieldingly to be retained in extended condition to reduce the effective outer diameter thereof, for free reception of the springy flighting within the hollow casing 11, as shown in FIG. 1. Conversely, upon rotation of the auger to project the flighting section 15 beyond the inner end of the casing 11, the pressure of the sliding bit 14 inwardly against the earth of the situs is effective yieldingly to contract the axial extent of the springy flighting 15, with resultant increase in the effective outer diameter of said flighting 15, for enlarging the formed pile cavity diameter in the area beyond the inner end of the casing 11, as shown at 17 in FIG. 2. In other words, by rotation of the auger in screwing direction while the flighting section 15 is free of the casing 11, a cavity extension 17 of selective depth can be defined, and all loosened earth is removed from the cavity and the casing along the auger flighting 10a and springy flighting 15. Upon release of the yielding downward pressure on the flighting 15, radially to contract the same, the auger can be axially withdrawn through the casing 11. The auger 10, however, may be rotated in screwing direction to fill the casing 11 and the bulb cavity 17 with fluid, selfhardenable cementitious material, such as cement mortar, after which the auger can be rotated in screwing direction while being progressively withdrawn from the casing,- through the retained fluid filler material therein. FIG. 3 shows the lower portionof a resultantly formed concrete or like pile body 19, with a tension rod 20 centered therein by being fed through the hollow auger shaft 12 and through a passage in the bit 14 while the cement is in fluid state.

In practice of the method of the invention generally as illustrated in FIGS. 1 to 3, for the purpose of forming a load carrying concrete pile, the tubular metal casing 11 is rammed or impacted vertically into the situs E to predetermined depth, while either simultaneously rotating a hollow shafted auger within the casing 11, as shown in FIG. 1, or by inserting and rotating the auger within the casing after it has been rammed to said predetermined depth. Upon full insertion of the casing, in any event, the auger 10 may be rotated in screwing direction to convey the earth outwardly from the easing, after which the auger may again be rotated while being forcibly pressed inwardly to turn the springy flighting 15 into the earth below the end of the casing, thereby to drill a bulb cavity 17 selective depth below the inner end of the casing. Upon so operating the auger the upward resistance of the earth against the parts of the auger extension 12a urges pilot bit 14 upwardly of the auger shaft, thereby to axially compress the spring flighting l5, and at the same time radially expand the same and cut the bulb cavity wall to an enlarged diameter, as shown at 17 in FIG. 2. After a bulb cavity 17 of desired depth and diameter is cut as described, fluid material, such as self-hardenable, hydraulic cement mortar may be fed down the casing, aided by rotation of the auger in screwing direction, until both the bulb cavity and the casing are fllled'to a desired level within the casing. While the filler material is still in a fluid state the auger may be removed through the'casing, by urging the auger upwardly within the casing while being rotated in screwing direction to keep the filler material solidly compressed as a unitary pile body, including an integral load bearing bulb as shown in FIG. 3. Where necessary or required a reinforcing element 20 or like device, such as a tie-rod or tension bar, may be provided as by lowering the same down the auger shaft 12, while the filler material P is still fluid, to be anchored in the pile body upon setting and hardening of the filler material (see FIG. 3).

Referring to FIGS. 4 and 5 there is illustrated provision and use of a modified form of bulb-forming means for use to practice above described method of the invention. In this form of the invention a hollow-shafted auger has a pilot bit 14a affixed on the lower end of the auger shaft 12, and slightly above the bit there is provided a fixed cross-member 21 having oppositely disposed cam slots 22, 22 within which a pair of cam-like cutters 23, 23 are pivoted. Each cutter 23 is shaped with reference to a corresponding slot 22 in the crosspiece 21 to be in a stop relationship with a stop portion 22a on the cross-member, when the cutter is pivoted radially inwardly, to contracted relationship (see FIG. 4), such pivoted action being accomplished by another cam surface 24 on the respective cutter 23 coming into engagement with the casing wall with upward movement of the auger in the casing (see FIG. 4). Conversely, upon downward movement of the auger in the casing, downwardly presented portions 25 of the cutters 23, by engaging and forcibly pressing against the earth of the situs, pivot the cutters upwardly to present cutting edges 24a of the same radially beyond the bottom edges of the casing, thereby to cut into the surrounding earth and define a bulb cavity 17a of greater diameter than the casing, as shown in FIG. 5. The depth of the bulb cavity 17a can be of any desired axial extent, and the loose earth may be removed from such cavity as by presenting the auger flighting somewhat beyond the desired bulb cavity depth for otherwise producing a pile body as shown in FIG. 3.

FIGS. 6 and 7 illustrate another form of bulb cavity cutting device, which may include a head portion 28 on which a plurality of rigid cutters 29 are in the form of peripherally spaced, resilient or springy blades extending axially inwardly and being normally yieldingly retained in radially inwardly compressed condition by engagement thereof with the inner wall surface of the casing, as shown in FIG. 6. Upon inward axial movement of the auger, whether rotating or not, the resilient blades are released from the casing yieldingly to expand radially for cutting an enlarged bulb forming cavity 17b, as shown in FIG. 7, and substantially in the manner of operation of the auger 10 as described in connection with FIGS. 4 and 5. 7

Referring to FIG. 8 there is illustrated another form of cavity cutting means operable in practice of the method generally as before. In this form of the invention, however, the auger is used in the above described manner, but is shown as having a fixed radially extending cutter 31 provided with a vertical cutting edge 32.

of lesser radial extent than the inner surface of the casing, and a second cutting blade 33 pivotally connected to the auger shaft to present cutting edge to define an enlarged cavity. A rod 34 connected to blade 33 is mounted to be shiftably extended upwardly along the auger shaft, and is adapted to be operable to pivot the blade 33 upwardly for reception within the casing for the purpose of withdrawing the auger through the casing, either before or after the method step of filling the casing and bulb cavity with pile forming material, as described above.

Other modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. A method of providing a pile or like body of selfhardenable cementitious material in an earth situs as for placing tiebacks or like members therein, comprising; the steps of providing a casing with a continuous flight auger rotatably and axially shiftably mounted therein, the auger having cutter means on the inner end thereof to be radially extendable and retractable by movement of the auger toward and from a projected position of the cutter means beyond the inner end of casing, driving said casing into the situs to define a bore of requisite depth, and rotating the continuous flight auger within saidcasing for removing earth from the defined bore along the auger flighting and through said casing; and further rotating said auger while said cutter means on an inner end thereof is projected beyond the inner end of the casing, with said cutter means radially extended to form an enlargement in the defined bore beyond said inner end of the casing.

2. A method as in claim 1 including feeding a supply of filler material inwardly through said casing to form a pile-like body in the bore and said enlargement thereof.

3. A method as in claim 2 said filler material being fluid, self-hardenable, cementitious material.

4. A method, as in claim 3, said casing being selectively removable from said defined bore after filling the bore with said filler material.

5. A method as in claim 4, said auger being removable from said filled bore by rotation thereof in unscrewing direction while the filler material is in unhardened condition. V

6. A method as in claim 2, said auger being removable from said filled bore by rotation of the same in unscrewing direction while the filler material is in unhardened condition.

7. Apparatus as for providing a pile or like body of self-hardenable cementitious material in an earth situs, comprising; a casing adapted to be driven into the situs to define a bore of requisite depth; a continuous flight auger rotatably and axially shiftably mounted within said casing for removing the earth through the same from the defined bore, with rotation of the auger in screwing direction; said auger having radially extendable and retractable cutter means at the inner end thereof, to be radially extended upon inward axial movement of the auger to present the cutter means beyond the inner end of the casing, for enlarging the radial extent of the defined bore with said rotation of the 6 auger; said cutter means upon retraction thereof permitting axial movement of the auger through said casing; means being provided for feeding fluid selfhardenable material through said casing to form a pilelike body in said bore and an enlargement thereof formed in said radial extent of said bore, said cutter means being radially extendable by said inward axial movement thereof into pressure engagement with earth of the situs at the inner end of the casing.

8. Apparatus as in claim 7, said cutter means being in the form of an axially compressible helical spring.

9. Apparatus as in claim 8, said helical spring forming an extension of said auger flighting.

10. Apparatus as in claim 7, said cutter means camlike surfaces engageable with said casing to contract cutter means for said movement thereof through the casing.

11. Apparatus as in claim 7, said cutter means including spring-like elements adapted to be yieldingly compressed radially inwardly for passagethereof through said shaft.

12. Apparatus as in claim 7, said cutter means including at least one pivoted element, and means selectively operable to pivot the same from and toward contracted relationship within said casing. 

1. A method of providing a pile or like body of self-hardenable cementitious material in an earth situs as for placing tiebacks or like members therein, comprising; the steps of providing a casing with a continuous flight auger rotatably and axially shiftably mounted therein, the auger having cutter means on the inner end thereof to be radially extendable and retractable by movement of the auger toward and from a projected position of the cutter means beyond the inner end of casing, driving said casing into the situs to define a bore of requisite depth, and rotating the continuous flight auger within said casing for removing earth from the defined bore along the auger flighting and through said casing; and further rotating said auger while said cutter means on an inner end thereof is projected beyond the inner end of the casing, with said cutter means radially extended to form an enlargement in the defined bore beyond said inner end of the casing.
 2. A method as in claim 1 including feeding a supply of filler material inwardly through said casing to form a pile-like body in the bore and said enlargement thereof.
 3. A method as in claim 2 said filler material being fluid, self-hardenable, cementitious material.
 4. A method, as in claim 3, said casing being selectively removable from said defined bore after filling the bore with said filler material.
 5. A method as in claim 4, said auger being removable from said filled bore by rotation thereof in unscrewing direction while the filler material is in unhardened condition.
 6. A method as in claim 2, said auger being removable from said filled bore by rotation of the same in unscrewing direction while the filler material is in unhardened condition.
 7. Apparatus as for providing a pile or like body of self-hardenable cementitious material in an earth situs, comprising; a casing adapted to be driven into the situs to define a bore of requisite depth; a continuous flight auger rotatably and axially shiftably mounted within said casing for removing the earth through the same from the defined bore, with rotation of the auger in screwing direction; said auger havIng radially extendable and retractable cutter means at the inner end thereof, to be radially extended upon inward axial movement of the auger to present the cutter means beyond the inner end of the casing, for enlarging the radial extent of the defined bore with said rotation of the auger; said cutter means upon retraction thereof permitting axial movement of the auger through said casing; means being provided for feeding fluid self-hardenable material through said casing to form a pile-like body in said bore and an enlargement thereof formed in said radial extent of said bore, said cutter means being radially extendable by said inward axial movement thereof into pressure engagement with earth of the situs at the inner end of the casing.
 8. Apparatus as in claim 7, said cutter means being in the form of an axially compressible helical spring.
 9. Apparatus as in claim 8, said helical spring forming an extension of said auger flighting.
 10. Apparatus as in claim 7, said cutter means cam-like surfaces engageable with said casing to contract cutter means for said movement thereof through the casing.
 11. Apparatus as in claim 7, said cutter means including spring-like elements adapted to be yieldingly compressed radially inwardly for passage thereof through said shaft.
 12. Apparatus as in claim 7, said cutter means including at least one pivoted element, and means selectively operable to pivot the same from and toward contracted relationship within said casing. 